Re: [PATCH v4 3/8] at91: dt: Add at91sam9261 dt SoC support

From: Nicolas Ferre
Date: Thu Feb 13 2014 - 03:11:18 EST

On 12/02/2014 20:47, Jean-Jacques Hiblot :
> Hi Alexandre,
>
> 2014-02-12 18:28 GMT+01:00 Alexandre Belloni
> <alexandre.belloni@xxxxxxxxxxxxxxxxxx>:
>> Hi,
>>
>> On 12/02/2014 at 11:06:42 +0100, Jean-Jacques Hiblot wrote :
>>> This patch adds support for the Device Tree on a sam9261-based platform
>>>
>>> Signed-off-by: Jean-Jacques Hiblot <jjhiblot@xxxxxxxxxxxxxxx>
>>> ---
>>> arch/arm/boot/dts/at91sam9261.dtsi | 740 +++++++++++++++++++++++++++++++++++++
>>> arch/arm/mach-at91/at91sam9261.c | 17 +
>>> 2 files changed, 757 insertions(+)
>>> create mode 100644 arch/arm/boot/dts/at91sam9261.dtsi
>>
>> [...]
>>
>>> +
>>> + apb {
>>> + compatible = "simple-bus";
>>> + #address-cells = <1>;
>>> + #size-cells = <1>;
>>> + ranges;
>>> +
>>> + tcb0: timer@fffa0000 {
>>> + compatible = "atmel,at91rm9200-tcb";
>>> + reg = <0xfffa0000 0x100>;
>>> + interrupts = < 17 IRQ_TYPE_LEVEL_HIGH 0
>>> + 18 IRQ_TYPE_LEVEL_HIGH 0
>>> + 19 IRQ_TYPE_LEVEL_HIGH 0
>>> + >;
>>> + clocks = <&tc0_clk>, <&tc1_clk>, <&tc2_clk>;
>>> + clock-names = "t0_clk", "t1_clk", "t2_clk";
>>> + };
>>> +
>>> + usb1: gadget@fffa4000 {
>>> + compatible = "atmel,at91rm9200-udc";
>>> + reg = <0xfffa4000 0x4000>;
>>> + interrupts = <10 IRQ_TYPE_LEVEL_HIGH 2>;
>>> + clocks = <&usb>, <&udc_clk>, <&udpck>;
>>> + clock-names = "usb_clk", "udc_clk", "udpck";
>>> + status = "disabled";
>>> + };
>>> +
>>> + mmc0: mmc@fffa8000 {
>>> + compatible = "atmel,hsmci";
>>> + reg = <0xfffa8000 0x600>;
>>> + interrupts = <9 IRQ_TYPE_LEVEL_HIGH 0>;
>>> + pinctrl-names = "default";
>>> + pinctrl-0 = <&pinctrl_mmc0_clk>, <&pinctrl_mmc0_slot0_cmd_dat0>, <&pinctrl_mmc0_slot0_dat1_3>;
>>> + #address-cells = <1>;
>>> + #size-cells = <0>;
>>> + clocks = <&mci0_clk>;
>>> + clock-names = "mci_clk";
>>> + status = "disabled";
>>> + };
>>> +
>>> + i2c0: i2c@fffac000 {
>>> + compatible = "atmel,at91sam9261-i2c";
>>> + pinctrl-names = "default";
>>> + pinctrl-0 = <&pinctrl_i2c_twi>;
>>> + reg = <0xfffac000 0x100>;
>>> + interrupts = <11 IRQ_TYPE_LEVEL_HIGH 6>;
>>> + #address-cells = <1>;
>>> + #size-cells = <0>;
>>> + clocks = <&twi0_clk>;
>>> + status = "disabled";
>>> + };
>>> +
>>> + usart0: serial@fffb0000 {
>>> + compatible = "atmel,at91sam9260-usart";
>>> + reg = <0xfffb0000 0x200>;
>>> + interrupts = <6 IRQ_TYPE_LEVEL_HIGH 5>;
>>> + atmel,use-dma-rx;
>>> + atmel,use-dma-tx;
>>> + pinctrl-names = "default";
>>> + pinctrl-0 = <&pinctrl_usart0>;
>>> + clocks = <&usart0_clk>;
>>> + clock-names = "usart";
>>> + status = "disabled";
>>> + };
>>> +
>>> + usart1: serial@fffb4000 {
>>> + compatible = "atmel,at91sam9260-usart";
>>> + reg = <0xfffb4000 0x200>;
>>> + interrupts = <7 IRQ_TYPE_LEVEL_HIGH 5>;
>>> + atmel,use-dma-rx;
>>> + atmel,use-dma-tx;
>>> + pinctrl-names = "default";
>>> + pinctrl-0 = <&pinctrl_usart1>;
>>> + clocks = <&usart1_clk>;
>>> + clock-names = "usart";
>>> + status = "disabled";
>>> + };
>>> +
>>> + usart2: serial@fffb8000{
>>> + compatible = "atmel,at91sam9260-usart";
>>> + reg = <0xfffb8000 0x200>;
>>> + interrupts = <8 IRQ_TYPE_LEVEL_HIGH 5>;
>>> + atmel,use-dma-rx;
>>> + atmel,use-dma-tx;
>>> + pinctrl-names = "default";
>>> + pinctrl-0 = <&pinctrl_usart2>;
>>> + clocks = <&usart2_clk>;
>>> + clock-names = "usart";
>>> + status = "disabled";
>>> + };
>>> +
>>> + ssc0: ssc@fffbc000 {
>>> + compatible = "atmel,at91rm9200-ssc";
>>> + reg = <0xfffbc000 0x4000>;
>>> + interrupts = <14 IRQ_TYPE_LEVEL_HIGH 5>;
>>> + pinctrl-names = "default";
>>> + pinctrl-0 = <&pinctrl_ssc0_tx &pinctrl_ssc0_rx>;
>>> + status = "disabled";
>>> + };
>>> +
>>> + ssc1: ssc@fffc0000 {
>>> + compatible = "atmel,at91rm9200-ssc";
>>> + reg = <0xfffc0000 0x4000>;
>>> + interrupts = <15 IRQ_TYPE_LEVEL_HIGH 5>;
>>> + pinctrl-names = "default";
>>> + pinctrl-0 = <&pinctrl_ssc1_tx &pinctrl_ssc1_rx>;
>>> + status = "disabled";
>>> + };
>>> +
>>> + spi0: spi@fffc8000 {
>>> + #address-cells = <1>;
>>> + #size-cells = <0>;
>>> + compatible = "atmel,at91rm9200-spi";
>>> + reg = <0xfffc8000 0x200>;
>>> + cs-gpios = <0>, <0>, <0>, <0>;
>>> + interrupts = <12 IRQ_TYPE_LEVEL_HIGH 3>;
>>> + pinctrl-names = "default";
>>> + pinctrl-0 = <&pinctrl_spi0>;
>>> + clocks = <&spi0_clk>;
>>> + clock-names = "spi_clk";
>>> + status = "disabled";
>>> + };
>>> +
>>> + spi1: spi@fffcc000 {
>>> + #address-cells = <1>;
>>> + #size-cells = <0>;
>>> + compatible = "atmel,at91rm9200-spi";
>>> + reg = <0xfffcc000 0x200>;
>>> + interrupts = <13 IRQ_TYPE_LEVEL_HIGH 3>;
>>> + pinctrl-names = "default";
>>> + pinctrl-0 = <&pinctrl_spi1>;
>>> + clocks = <&spi1_clk>;
>>> + clock-names = "spi_clk";
>>> + status = "disabled";
>>> + };
>>> +
>>> + ramc: ramc@ffffea00 {
>>> + compatible = "atmel,at91sam9260-sdramc";
>>> + reg = <0xffffea00 0x200>;
>>> + };
>>> +
>>
>> You probably copied/pasted it but according to the block diagram, the
>> sdram controller is not under the apb.
> You're right I copied/pasted :o) But the addresses of the registers
> look like typical APB addresses.
> AFAIK all the registers of this SOC are accessed through the APB
> (except for OHCI and LCDC)

Yes, that is the point: if the register bank appears as an APB address,
I place it on the APB bus.
The other master interfaces (on AHB) are the ones that the IP uses, not
us from the CPU point of view...

So I think that Jean-Jacques DT is okay concerning this.

> So probably the real question here is what is the sense of the bus
> hierarchy in cases where a controller is connected to several buses
> (APB for registers, AHB/matrix for other purpose) ?
> As I don't have any idea on how to handle this, I choose to copy/paste.
>
>>
>>> + matrix: matrix@ffffee00 {
>>> + compatible = "atmel,at91sam9261-bus-matrix";
>>> + reg = <0xffffee00 0x200>;
>>> + };
>>> +
>>
>> Same here, the apb is actually under the bus matrix.
>>
>> I don't know whether it can be represented another way though.
>>
>>
>> --
>> Alexandre Belloni, Free Electrons
>> Embedded Linux, Kernel and Android engineering
>> http://free-electrons.com
>
>


--
Nicolas Ferre
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